JP2003213700A - Rubber bearing and pile head structure - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a rubber bearing and pile head structure capable of reducing a bending moment generated in the connecting part between an upper structure and a lower structure with a simple structure. <P>SOLUTION: This structure comprises a protruding upper bearing part 11 fixed to the lower part of a footing 1, a recessed lower bearing part 12 fixed to the head part of a foundation pile 2, a columnar or cylindrical bearing rubber 13 consisting of a rubber elastic body excellent compression restorability, which is arranged between the upper bearing part 11 and the lower bearing part 12. The bearing rubber 13 supports the upper structure and absorbs a rotation around the axis. Further, a side receiving rubber 14 is arranged between the circumferential surface of the protruding part 11m of the upper baring part 11 and the inside surface of the recessed part 12m of the lower bearing part, whereby a horizontal force acting in an earthquake or the like is absorbed. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to, for example, a structure of a rubber bearing inserted between an upper structure and a lower structure supporting the structure and a pile foundation for earthquake resistance, vibration control, and seismic isolation. The present invention relates to a pile head structure of a structure that the user has.

[0002]

2. Description of the Related Art In recent years, in order to take measures against earthquakes, seismic control, and seismic isolation, it has been common practice to join upper structures such as buildings and bridge girders with underlying structures such as foundation piles and bridge piers Instead of the rigid joint, a semi-rigid joint, a pin joint, or a joining method using a rolling bearing, a sliding bearing, a sealed rubber bearing, or the like has been adopted. FIG. 8 shows, for example, Japanese Patent Laid-Open No. 2001-
It is a figure which shows the outline | summary of the pile foundation structure using the closed rubber bearing described in 107377 gazette, in which the convex lower shoe 5 is attached to the head of the concrete foundation pile 51 through the mortar seat 52.
3 is fixed, and a disk-shaped rubber elastic body 54 is mounted on this, and the rubber elastic body is attached to the lower part of the reinforced concrete footing (structure foundation) 55 facing the head of the foundation pile 51. The concave upper shoe 56 corresponding to the shape of the convex lower shoe 53 including 54 is fixed, and the upper shoe 56 and the lower shoe 53 are fitted to each other, and the head of the foundation pile 51 and the footing are 55 is joined to the rubber elastic body 5 so that the bending moment generated at the joint portion between the upper structure and the lower structure, which acts due to an earthquake or the like, can be applied.
It is designed to be absorbed by the deformation of 4. Reference numeral 57 denotes an outer peripheral position of a fitting portion between the upper shoe 56 and the lower shoe 53, specifically, a position where the outer circumferential surface of the lower shoe 53 comes into contact with the lower surface of the rubber elastic body 54, and is projected. Mold lower shoe 53 and concave upper shoe 5
6, the rubber elastic body 5 from the gap formed in the fitting portion
It is a seal ring material for preventing the outflow (protrusion) of No. 4

[0003]

By the way, in the above-mentioned conventional sealed rubber bearing, in order to suppress the generation of the bending moment between the head of the foundation pile 51 and the footing 55,
The convex lower shoe 53 or the concave upper shoe 56 is rotated in the vertical direction as shown by the arrow in the figure (the upper shoe 56 is the lower shoe 5).
It is necessary to provide a certain amount of clearance in the fitting portion so that the tilt portion 3 can be freely rotated. However, since the sealed rubber bearing has a structure in which the convex lower shoe 53 and the concave upper shoe 56 are fitted to each other, it is difficult to set the design of the gap and the installation location of the seal ring material 57, and bending due to rotation is difficult. It was difficult to simultaneously achieve the absorption of the moment and the outflow prevention of the rubber elastic body 54. In addition, FIG.
As shown in FIG. 3, a metallic piston 63 and a rubber elastic body 64 are arranged between the concave lower shoe 61 and the flat upper shoe 62, and the lower shoe 61 and the upper shoe 62 are A rubber bearing having a structure provided with a gap that allows the shoe 61 or the upper shoe 62 to rotate in the vertical direction (Japanese Utility Model Publication No. Sho 56-3367) has been proposed in the past, but the piston 63 and the seal ring material 65, Since the structure is complicated because it is necessary to attach 66, and the structure in which the seal ring members 65 and 66 are arranged in the peripheral edge portion of the rubber elastic body 64, the peripheral edge portion of the rubber elastic body 64 becomes thin and the rubber elastic body There is a problem that 64 is easily deteriorated.

The present invention has been made in view of the conventional problems, and is a rubber bearing and a pile head capable of reducing a bending moment generated at a joint portion between an upper structure and a lower structure with a simple structure. It is intended to provide a structure.

[0005]

As a result of intensive studies, the present inventor has found that vertical load (compressive force) and horizontal load (compressive force) acting between the upper structure or its foundation and the head of the lower structure ( It has been found that the bending moment generated at the joint portion between the upper structure and the lower structure can be effectively reduced by receiving (shearing force) by separate elastic members, and the present invention has been achieved. . That is, the rubber bearing according to claim 1 of the present invention comprises a concave lower bearing portion fixed to the head of the lower structure and a lower bearing portion fixed to the lower portion of the upper structure or its foundation. An upper structure is provided by the rubber elastic body by providing an upper bearing portion having a convex portion protruding into the concave portion and a rubber elastic body arranged between the concave portion of the lower bearing portion and the convex portion of the upper bearing portion. By supporting an object and absorbing vertical rotation, by providing an elastic member arranged between the outer peripheral side of the convex portion of the upper bearing and the inner peripheral side of the concave portion of the lower bearing. , Is designed to absorb the horizontal force that acts during an earthquake, etc.
The degree of freedom in selecting the spring constant of the rubber elastic body and the elastic member is increased, and the rotational deformation of the joint portion can be effectively absorbed, so that the bending moment acting on the pile head can be significantly reduced.

According to a second aspect of the present invention, in the rubber bearing, the rubber member and the steel plate are alternately laminated from the outer peripheral side of the convex portion of the upper bearing portion to the inner peripheral side of the concave portion of the lower bearing portion. It is made of laminated rubber. Since the horizontal force acting on the laminated rubber is perpendicular to the laminating direction of the laminated rubber, it acts as a compressive force on the laminated rubber, so that a large horizontal force can be received. Further, since the spring constant and the number of stacked layers of the rubber member can be appropriately selected, it is possible to reliably absorb the horizontal force acting between the upper structure or the foundation thereof and the head of the lower structure. In the rubber bearing according to claim 3, the elastic member is composed of a spring member that expands and contracts in a direction extending from the outer peripheral side of the convex portion of the upper bearing portion to the inner peripheral side of the concave portion of the lower bearing portion. is there. In the rubber bearing according to claim 4, the upper side of the rubber elastic body is embedded and fixed in the upper bearing member and the lower side is embedded in the lower bearing member, respectively, thereby suppressing axial displacement of the rubber elastic body. Is possible. In addition, the pile head structure according to claim 5 is a structure having a pile foundation, wherein an upper structure or a lower portion of the foundation and a head portion of the pile foundation are included in any one of the above claims 1 to 4. It is joined using the rubber bearing described in.

Further, in the pile head structure according to the sixth aspect, a rubber elastic body is arranged between the head of the lower structure and the bearing member fixed to the lower part of the upper structure or the foundation thereof, and On the outer peripheral side of the head of the structure, a side wall portion is provided which is spaced a predetermined distance from the outside of the rubber elastic body and protrudes upward. An elastic member is provided between the side wall portion and the outer peripheral side of the support member. Is arranged. The pile head structure according to claim 7 is the pile head structure according to claim 6, wherein the elastic member is formed by alternately stacking a rubber member and a steel plate from the outer peripheral side of the bearing member toward the side wall portion. It is made of rubber or a spring member that expands and contracts in the direction extending from the outer peripheral side of the support member toward the side wall portion.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. Embodiment 1. FIG. 1 is a schematic diagram showing the basic structure of a rubber bearing 10 according to the first embodiment. In FIG.
Is a convex upper bearing portion fixed to the lower part of the footing (structure foundation) 1, 12 is a concave lower bearing portion fixed to the head of the foundation pile 2, and 13 is the upper bearing portion 11 and the lower bearing. A cylindrical or cylindrical bearing rubber made of a rubber elastic body having excellent compression and restoration properties, which is disposed between the lower support portion 12 and the outer peripheral surface of the convex portion 11m of the upper support portion 11. 12m recess
It is a side bearing rubber that is disposed between the inner peripheral surface of the bearing rubber 13 and the outer peripheral surface of the bearing rubber 13. In this example, a predetermined clearance g is provided between the base portion (flange portion) 11n of the upper bearing portion 11 and the upper end portion of the side wall portion 12n of the lower bearing portion 12 to rotate in the vertical direction (the upper bearing portion 11 is lowered. It is possible to freely rotate it so as to tilt it with respect to the support portion 12.

Next, the operation of the rubber bearing 10 will be described. The bearing rubber 13 arranged between the upper bearing portion 11 attached to the footing 1 and the lower bearing portion 12 attached to the head of the foundation pile 2 is a rubber for supporting the upper structure. Is subjected to a vertical load F ₁ as shown in FIG. In this example, since the side bearing rubber 14 is arranged around the bearing rubber 13, the bearing rubber 13 is a closed rubber. Therefore, the support performance of the structure can be improved as compared with the case where only the bearing rubber 13 is used. When the inertial force (horizontal force) F ₂ of the upper structure acts during the earthquake, the horizontal force F ₂ is
Since it is transmitted to the head of the foundation pile 2 via the side bearing rubber 14, the horizontal force F ₂ is absorbed by the side bearing rubber 14 and the horizontal force between the footing 1 and the head of the foundation pile 2 is absorbed. The displacement can be reduced. Further, by using the rubber elastic body (the bearing rubber 13 and the side bearing rubber 14), it is possible to absorb the rotational deformation at the joint portion between the footing 1 and the head portion of the foundation pile 2 and to act on the joint portion. The bending moment M can be reduced. Further, since the bearing rubber 13 receives the vertical load acting between the footing 1 and the head of the foundation pile 2, and the side bearing rubber 14 receives the horizontal load, the bearing rubber 13 and the side bearing rubber 14 are The degree of freedom in selecting the spring constant is increased, and the rotational deformation of the joint can be effectively absorbed. Further, in the event of an earthquake, a pulling load (lifting force) may be applied to the bearing rubber 13, and in this case, the side receiving rubber 14 can resist the pulling load.

FIG. 3 is a view showing an example of a pile head structure using a rubber bearing according to the present invention. This rubber bearing 10A has a convex upper bearing portion 11A, a concave lower bearing portion 12A and a compression restoring property. It has a bearing rubber 13 made of a rubber elastic body excellent in heat resistance, and a laminated rubber 14A which is a side bearing rubber disposed between the inner peripheral surface of the lower bearing portion 12A and the outer peripheral surface of the upper bearing portion 12A. . The lower support 12A is a disk-shaped base (flange)
12a and a cylindrical portion 12b protruding upward (in the footing 1 direction) from the base 12a.
A cylindrical recess 12c for embedding and fixing the lower portion of the bearing rubber 13 is formed inside the cylindrical portion 12b of a. Further, the upper bearing portion 11A projects downward from the disk-shaped base (flange portion) 11a and the lower surface side (lower bearing portion 12A side) of the base 11a, and the outer diameter of the cylindrical portion 12b. It consists of a cylindrical part 11b smaller than the inner diameter,
A cylindrical hole 11p is formed below the column 11b, and a cylinder for burying and fixing the upper portion of the bearing rubber 13 at a position corresponding to the recess 12c inside the hole 11p. Shaped concave portion 11c is formed. In addition, the base 12a of the lower support portion 12A and the cylindrical portion 1 of the upper support portion 11A.
1b and the tip portion of 1b, and the cylindrical portion 1 of the lower bearing portion 12A
Between the tip of 2b and the base 11a of the upper bearing 11A, the vertical rotation (upper bearing 11A is lower bearing 12A).
A predetermined clearance is provided so as to freely rotate (tilt with respect to).

The bearing rubber 13 is formed by adhering a steel plate 13b on the upper surface of a rubber elastic body 13a and a steel plate 13c on the lower surface. The lower part of the bearing rubber 13 is embedded and fixed in the recess 12c, and the upper part is in the recess 11c. It is embedded and fixed. As a result, the bearing rubber 13 has the footing 1 in the thickness direction.
It contracts under the vertical load acting between the head and the head of the foundation pile 2, but with respect to horizontal load, since the upper and lower parts are embedded and fixed in the upper bearing part 11A and the lower bearing part 12A, respectively, It is possible to suppress axial displacement due to load. The laminated rubber 14A, which is a side bearing rubber, is attached to the outer peripheral side of the cylindrical portion 11b of the upper bearing portion 11A and the inner peripheral side of the cylindrical portion 12b of the lower bearing portion 12A. At this time, the rubber member 14a and the steel plate 14b constituting the laminated rubber 14A are moved from the outer peripheral side of the convex portion of the upper bearing portion 11A to the inner peripheral side of the concave portion of the lower bearing portion 12A (the cylindrical portion 11b and the cylindrical portion 12b are formed). It is laminated alternately in the radial direction. As a result, the horizontal force acting on the laminated rubber 14A becomes perpendicular to the laminating direction of the laminated rubber 14A and acts as a compressive force on the laminated rubber 14A, so that a large horizontal load can be received. Therefore, the axial displacement of the bearing rubber 13 due to the horizontal load can be suppressed.

As a result, even if the inertial force (horizontal load) of the upper structure acts during an earthquake, the laminated rubber 14A can effectively absorb the horizontal displacement, and the footing 1 and the foundation pile 2 can be effectively absorbed. It is possible to absorb the rotational deformation at the joint portion with the head portion, and to reduce the bending moment acting on the joint portion.

Embodiment 2. FIG. 4 is a diagram showing an example of a pile head structure using the rubber bearing 20 according to the second embodiment. In the rubber bearing 20 of this example, a disk-shaped steel plate 21 is attached to the head of the foundation pile 2 instead of the lower bearing portion 12 of the first embodiment.
In addition to mounting, a cylindrical steel pipe 22 mounted on the steel plate 21 and having a laminated rubber 23 disposed on the inner wall side is provided on the outer peripheral side of the convex portion 11m of the upper support portion 11 and the base portion 11n of the upper support portion 11 is provided in a predetermined manner. It is arranged with a gap of
A packing rubber 24 is arranged between the outer peripheral portion of the bearing rubber 13 and the laminated rubber 23. This makes it possible to absorb the horizontal force that acts during an earthquake with a simple configuration, and footing 1
It is possible to reduce the bending moment that acts on the joint between the head of the foundation pile 2 and the base pile.

Embodiment 3. In the first and second embodiments described above, the horizontal force acting during an earthquake is received by the side receiving rubber 14 and the laminated rubbers 14A and 23.
As shown in (a) and (b), a rubber bearing having a structure in which the side surface of the cylindrical portion 11b of the upper bearing portion 11A and the inner peripheral side of the cylindrical portion 12b of the lower bearing portion 12A are coupled by a plurality of coil springs 31. Even if the footing 1 and the head of the foundation pile 2 are connected by using 30, the same effect can be obtained. At this time, it is desirable that the coil springs 31 are attached at least at three places so as to be equally divided circumferentially with respect to the centers of the upper and lower bearing portions 11A and 12A. Also,
As shown in FIG. 6, instead of the coil spring 31, a plurality of leaf springs 32 are used to connect the side surface of the cylindrical portion 11b of the upper bearing portion 11A and the inner peripheral side of the cylindrical portion 12b of the lower bearing portion 12A. Good.

Fourth Embodiment FIG. 7 is a diagram showing an example of a pile head structure according to the fourth embodiment. In the pile head structure of this example, a convex upper support portion 41 is attached to the lower part of the footing 1, and the upper and lower surfaces of the rubber elastic body 42a are provided between the upper support portion 41 and the head of the foundation pile 2. The bearing rubber 42 fixed by the steel plates 42b and 42c is arranged, and a cylindrical steel pipe 43 is driven on the outer peripheral side of the head of the foundation pile 2 at a predetermined distance to the outside of the bearing rubber 42. An elastic member (here, laminated rubber) 44 is arranged between the inner wall side and the outer peripheral side of the cylindrical portion 41b of the upper support portion 41. Thereby, with a simple structure, the horizontal displacement due to the horizontal force acting at the time of an earthquake can be absorbed by the elastic member 44, and the bending moment acting on the joint between the footing 1 and the head of the foundation pile 2 can be reduced. .

[0016]

As described above, according to the rubber bearing of the present invention, the rubber elastic body is arranged between the convex portion of the upper bearing portion and the concave portion of the lower bearing portion, or the upper structure or its foundation and lower structure. Supports a vertical load acting between the head of the object and absorbs the vertical rotation, and the outer peripheral side of the convex portion of the upper bearing portion and the inner peripheral side of the concave portion of the lower bearing portion. Since the elastic member is arranged between them to absorb the horizontal load, the rotational deformation of the joint portion can be effectively absorbed, and the bending moment acting on the pile head can be significantly reduced. Also, by bending the upper structure of the structure having the pile foundation or the lower part of the foundation and the pile foundation head by using the rubber bearing having the above-mentioned configuration, the bending moment generated at the joint portion can be surely reduced. It is possible to realize a pile head structure that can be used.

[Brief description of drawings]

FIG. 1 is a diagram showing a basic configuration of a rubber bearing according to a first embodiment of the present invention.

FIG. 2 is a view for explaining the action of the rubber bearing of the present invention.

FIG. 3 is a diagram showing an example of a pile head structure using the rubber bearing of the present invention.

FIG. 4 is a diagram showing a configuration of a rubber bearing according to the second embodiment.

FIG. 5 is a diagram showing a configuration of a rubber bearing according to the third embodiment.

FIG. 6 is a view showing another structure of the rubber bearing according to the present invention.

FIG. 7 is a diagram showing a pile head structure according to a fourth embodiment.

FIG. 8 is a view showing a conventional pile head structure.

FIG. 9 is a diagram showing a configuration of a conventional rubber bearing.

[Explanation of symbols]

1 footing, 2 foundation piles, 10 rubber bearings, 11
Upper bearing, 11m Projection of upper bearing, 11n Base of upper bearing, 12 Lower bearing, 12m Recess of lower bearing, 1
2n Side wall of lower bearing, 13 bearing rubber, 14 bearing rubber, g clearance.

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Kenichi Takizawa             4-53 Kitahama, Chuo-ku, Osaka City, Osaka Prefecture             Sumitomo Metal Industries, Ltd. (72) Inventor Hiroshi Kida             4-53 Kitahama, Chuo-ku, Osaka City, Osaka Prefecture             Sumitomo Metal Industries, Ltd. (72) Inventor Toshihiro Mori             No. 2 Tsukutocho, Shinjuku-ku, Tokyo Co., Ltd.             Kumagai Gumi Tokyo Head Office (72) Inventor Norio Watanabe             No. 2 Tsukutocho, Shinjuku-ku, Tokyo Co., Ltd.             Kumagai Gumi Tokyo Head Office (72) Inventor Michio Kitawaki             2-4-9 Umeda, Kita-ku, Osaka City, Osaka Prefecture             Ryo Rubber Co., Ltd. Osaka Headquarters F-term (reference) 2D046 CA03 DA11 DA13

Claims (7)

[Claims] 1. An upper part having a concave lower bearing part fixed to the head of the lower structure and a convex part projecting into the concave part of the lower bearing part fixed to the lower part of the upper structure or its foundation. A support part, and a rubber elastic body arranged between the concave part of the lower support part and the convex part of the upper support part are provided, and the outer peripheral side of the convex part of the upper support part and the concave part of the lower support part. A rubber bearing having an elastic member arranged between the inner peripheral side and the inner peripheral side. 2. The elastic member is made of laminated rubber in which a rubber member and a steel plate are alternately laminated from the outer peripheral side of the convex portion of the upper bearing portion to the inner peripheral side direction of the concave portion of the lower bearing portion. The rubber bearing according to claim 1, which is characterized. 3. The elastic member is composed of a spring member that expands and contracts in a direction extending from the outer peripheral side of the convex portion of the upper bearing portion to the inner peripheral side of the concave portion of the lower bearing portion. The rubber bearing described. 4. The rubber bearing according to claim 1, wherein an upper side of the rubber elastic body is embedded and fixed in an upper bearing member and a lower side thereof is embedded in a lower bearing member. 5. In a structure having a pile foundation, an upper structure or a lower portion of the foundation and a head portion of the pile foundation,
A pile head structure, which is joined using the rubber bearing according to any one of claims 1 to 4. 6. A rubber elastic body is arranged between the head of the lower structure and a support member fixed to the lower part of the upper structure or its foundation, and on the outer peripheral side of the head of the lower structure,
A pile head characterized in that a side wall portion protruding upward is provided at a predetermined distance from the outside of the rubber elastic body, and an elastic member is arranged between the side wall portion and the outer peripheral side of the support member. Construction. 7. A laminated rubber in which a rubber member and a steel plate are alternately laminated from an outer peripheral side of a supporting member toward a side wall portion, or a direction in which the elastic member extends from the outer peripheral side of the supporting member toward a side wall portion. The pile head structure according to claim 6, wherein the pile head structure is configured by a spring member that expands and contracts in a horizontal direction.